1. Field
Embodiments of the present invention relate to an information processing device and a method for controlling a viewing angle.
2. Description of the Related Art
In recent years, liquid crystal display devices have been widely used as display devices for notebook type computers, monitors or the like. Improvements in viewing angle dependency of the liquid crystal display device has progressed and the viewing angle with the same level as that of a CRT has been achieved for the liquid crystal display device.
However, it is important for a display device, for the use of a mobile terminal, etc., to allow a user to view displayed items from the front direction and to make the display device hard to be viewed from the oblique direction. This is because, when confidential documents or the like are prepared or read in a public place and the like, the display device intends to prevent persons other than the user from viewing displayed documents or the like. Hence, the display device is structured to allow the user located in front of the display device to read or write a personal mail without caring about the surroundings.
As for a technique to control the viewing angle, a technique using a liquid crystal panel (hereinafter, referred to as a viewing angle control filter) is disclosed (refer to Jpn. Pat. Appln. KOKAI Publication No. 2004-133334). In the technique described in the aforementioned patent document, when the control filter is turned on, a blocking pattern is viewed from the obliquely front direction to protect information on a screen such as a text. Further, even when the control filter is operated, the manner of viewing from the front is not changed. When the control filter is turned off, the user can view the screen with an original viewing angle of an image display panel for displaying images.